CNC Machine with Granite Structure

CNC machined Granite Structure

Making a fast, high-accuracy CNC machine requires a rigid and stable structure. In this capacity, granite outperforms casting iron. A casting-iron body challenges a CNC machine’s stability and rigidity. Relieving casting’s internal stresses are always a source of unexpected changes in the geometry of the machine. In contrast, because granite has been formed by nature over hundreds of millions of years, it will never change its form over time.

Granite’s thermal expansion also is 25% lower than casting iron’s, meaning it maintains its accuracy much better in different temperatures. Granite further dampens any vibration almost 10 times faster than steel or cast iron does. This lets the machine operate more smoothly through in high speeds or in its spindle-cutting force.

Acceleration is vital in high-speed machining. High-vibration absorption improves the machine’s rigidity and powers its axes with much greater velocity and acceleration. A granite-structure machine with the same dimensions as a steel or cast-iron unit can speed up three times faster. For example, to produce at a higher rate, intricate designs of small parts in the micro-machining process require high acceleration on the corners. Otherwise, starting and stopping on every corner will waste valuable time. In addition, if the machine is not rigid enough, high acceleration can cause the axes’ movements to overshoot and destroy the sophisticated tool paths. All of these factors make granite a preferable choice for high-speed machining.

Linear Motors with no backlash

Employing granite structure for the body of the machine allows us to use linear motors where there is no ballscrew for motion. Ballscrews or virtually any screw will inherently has backlash. Linear motors on the other hand introduces no backlash. It is all electronic commutation on the magnetic pols and no mechanical junction in between. This would allow the machine to accelerate much faster and also eliminates any inconsistency of the screw geometry. Machine would move much smoother and much more responsive.

To discuss more about price, delivery time and customizing the product, please contact us